Improvement in piano-forte actions



T. P. CARR.

Piano-Forte Actions.

UNITED STATES PATENT CFFICE.

THADDEUS I. CARE, OF YELLOW SPRINGS, OHIO.

IMPROVEMENT lN PIANO-FORTE ACTIONS.

Specification forming part of Letters Patent No. 165,304, dated June 6,1875; application filed May 6, 1875.

To all whom it may concern:

Be it known that I, THADDEUS P. CARR, of Yellow Springs, Greene county,Ohio, have invented a new and useful Piano-Forte Action, of which thefollowing is a specification This invention relates to that class ofdevices commonly known as double-repeating piano-actions; andmyimprovement consists in a novel arrangement of back-catch forsustaining the hammer in its elevated position theinstant the lattercomes in contact with the wire,

the peculiar construction of said back-catch,

together with its mode of operation, being hereinafter fully described.

In the accompanying drawing, Figure 1 is a partially-sectionizedelevation of my improved double repeating action, the hammer being shownin its normal or depressed position. Fig.2 is another sectionizedelevation of the action, showing the hammer raised and in contact withthe wire of the instrument. Fig. 3 represents a modified form of thebackcatch.

A represents a portion of the bed ot'a pianoaction, said bed having thecustomary cushion a, and a bearing, B, to which latter the key 0 ispivoted in the usual manner. D and E represent, respectively, two rails,which extend longitudinally of the action, the former being providedwith a cushion, cl, while the latter has attached to it theknuckle-jointed bearing 0 of the shaft G, that is secured to shank orstem H of hammer I. J is the jaw of this hammer. K is the jack, hingedat It to an adjustable bearing, L, secured to the upper side of key 0. Mis a set-screw, which regulates the action of thejack. All of theabove-enumerated devices may be of the represented or any other approvedconstruction, as they constitute no part of my invention.

Myimprovement begins with the back-catch N, which device, instead ofbeing rigidly united to a stem projecting upwardly from the key 0 in theusual manner, is pivoted at O to a bent lover or bell-crank, P, thelatter being hinged at p to a bearing, B. This bearing is secured to,and adjusted upon, the key 0 by means of screws r. The back-catch has aheel, a, to which is secured one end of a suitable spring, S, the otherend of said spring being attached to the lever P at any convenientpoint. The stress of this spring tends to throw the free end ofback-catchN outwardly, or away from its supportinglever P, which cutwardmovement is restricted by an adjustable stop, 1., that engages with ascrew threaded rod, T. This rod projects inwardly from the back-catch ofthe action, and traverses a slot, Q, in lever P, as seen in Fig. 1. Thebent lever or bell crank P has a toe, U, which, as soon as the outer endof key 0 is depressed by the performers finger, is brought in contactwith a cushioned tripper, V, said tripper being adjusted to the underside of cushionrail 1) by screws v. V is the appropriate wire for hammerI to act against.

The operation of my action is as follows: In the normal position of thevarious parts the hammer-shaft Gr rests upon the cushion d, and theoperating end of jack K is engaged under the jaw of the hammer, whilethe lever P, that supports the back-catch N, turns upon the pivot 19,and falls rearwardly as far as the bearing R will permit, as seen inFig. 1. .By referring to this illustration it will be noticed that thehammer-shank H is not in contact with any member of the movement, and,consequently, it is free to act the moment the player strikes the key ofthe instrument, thus insuring prompt action in response to a light touchot'thekey. The instantthe key Ois struck the ditierent members of theaction assume the position shown in Fig. 2, the hammer being at onceelevated and struck against the appropriate wire N. This movement of thekey brings the toe U in contact with the tripper V, thereby swinginglever P forward, and

causing the cushioned back-catch N to engage under the chamfered edge ofhammer-shank H at the moment of striking the wire, as seen in Fig. 2.

It is evident that the back-catch will sustain the hammer in thiselevated position as long as the key is under pressure of the playersfinger; but the moment the operator relaxes the pressure in the leastdegree, and allows the operating end of the key to descend to anyappreciable extent, that moment the jack K re-engages with the jaw J ofthe hammer, as indicated by dotted lines in Fig. 2.

This re-engagement of the jack with the hammers jaw enables theperformer to quickly repeat the note without releasing the key.

This quick re-engagementof the jack K with the jaw J is accomplished bythe spring S forcing the catch N outwardly with sufficient pressure toenable said back-catch to sustain the hammer in its elevated position.As the hammer is thus prevented from dropping, it is evident that a veryslight movement of the key will suffice to enable the engagement ofthejack with thejaw.

In applying my action to the piano the stop T t and tripper V a mustfirst be properly adjusted, so as to allow the hammer I to fall a slightdistance from the wire before the backcatch N engages with its shank.This slight recoil of the hammer is necessary, as it is evident that itsprolonged contact with the wire would prevent the proper vibration ofthe latter and thereby detract from the musical qualities of theinstrument.

Chief among the advantages of this action are its delicacy, promptness,and ease of operation, its simplicity and durability. The action can beput into a piano for a small fraction of the cost of otherdouble-repeating actions now in use, and quite equal or excel them ineffectiveness. As to durability, the parts are so few and so simple inconstruction-there being only two bearings and two pivotsit can be madeequally as durable as the parts without this attachment; such, forexample, as the French grand action now used in all square pianos.

In perfectness of operation my action is believed to be superior to anydouble-repeating action now used. In every variety of touch that aplayer may use, my action operates as completely as any double-repeatingaction that is made, and in one respect more completely. In my action,however hard the key may be struck, the hammer will not rebound so farfrom the string but what thejaek will get back to its place under thejaw of the hammer before the key under the finger of the player risesany appreciable distance. In all other doublerepeating actions known tome, when the key is struck with considerable force the hammer reboundsand catches on the stationary back-catch, and then the key will have torise under the finger to a level with the others before the jack canreturn to its startingplace, so that these actions are practically of noaccount except in very light delicate playing.

My invention is more especially designed as an eliective doublerepeatingaction for square pianos. When put into grand pianos the parts will haveto be shaped difi'erently, though oc cupying the same relativepositions. As the grand-piano action is some two or three inches higher,the jack will have to be longer, and then the other parts will have tobe changed accordingly. Thus the lever P would have a slightly diiferentshape with its pivot or fulcrum p nearer the end of the key and thebearing nearer the end of the hammer, thus making the lever P almoststraight. These and other changes in proportions and dimensions will bemade without difficulty by any competent action-maker.

M y action has another important advantage in being easy to regulate;any tuner can regulate it without trouble. It has another greatadvantage also in the tuner being able to take out the key easily. Inother doublerepeating actions the tuner has to tear the action almost topieces before the key can be taken out.

It will be seen that the bearing of the heel of the lever against thecushion V operates to make the back-catch touch the hammer at the momentof striking the wire. If it touched the hammer before that moment, thetouch would be effected and the object be not perfectly attained.

As my peculiarly-constructed swinging or pivoted back-catch is theleading feature of my invention, I have shown in Fig. 3 another way ofapplying said device to the instrument. In this arrangement the bentlever P is pivoted to a bearing, X, which latter is secured to a rail,Y. The toe U of said lever is acted upon by a tripper, V, attached tothe key and not to the cushion-rail, as in the previous illustrations.

Other modifications of the hinged backcatch may be arranged so as to beadapted to various constructions of pianos.

I claim as new and of my invention- In combination with a piano-key, O,hammer G H I J, and jack K k, the pivoted adjustable back-catch N a O S,and lever I? U, which latter is pivoted either to the block R or bearing X, and operated by the tripper V or V, sub stantially as hereindescribed and set forth.

In testimony of which invention I hereunto set my hand.

Attest: THADDEUS P. CARR.

A. W. OoNovEn, A. F. HOPKINS.

